Pressing buttons multiple times loads multiple pages (Android)

I'm having an issue with Android navigation. I have a list view that contains a bunch of items that have tapped events. These tapped events look like this:

    async void Tab_ItemSelected(object sender, ItemSelectedEventArgs e)
    {
        var details = new DetailPage(e.SelectedItem.ID);
        await Navigation.PushAsync(details);
    }

This works on iOS and Windows Phone just fine, but if you're quick enough, it will load two detail pages onto the stack. This also seems to occur quite a few places on our Android application. Is there any way around this?